HighFix available
xorg-server, xwayland — security advisory
A flaw was found in xorg-x11-server in versions before 21.1.2 and before 1.20.14. An out-of-bounds access can occur in the SwapCreateRegister function. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
- Products
- xorg-server, xwayland
- Affected versions
- Not specified
- Fixed versions
- 2:1.20.13-3, 2:21.1.4-1
- CVEs
- CVE-2021-4011
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 00:40 UTC · Revision 1
Source evidence
A flaw was found in xorg-x11-server in versions before 21.1.2 and before 1.20.14. An out-of-bounds access can occur in the SwapCreateRegister function. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
osv:DEBIAN-CVE-2021-4011
xorg-server
Fixed versions: 2:1.20.13-3
xorg-server
Fixed versions: 2:1.20.13-3
xorg-server
Fixed versions: 2:1.20.13-3
xwayland
Fixed versions: 2:21.1.4-1
xwayland
Fixed versions: 2:21.1.4-1
xwayland
Fixed versions: 2:21.1.4-1
Complete source record
{
"id": "839946bb2fe48976f8ab909c10004a157ae5acb250d9a57dc680344b26850b38",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2021-4011",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2021-4011",
"summary": "A flaw was found in xorg-x11-server in versions before 21.1.2 and before 1.20.14. An out-of-bounds access can occur in the SwapCreateRegister function. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.",
"evidence": "osv:DEBIAN-CVE-2021-4011",
"products": [
{
"name": {
"value": "xorg-server",
"evidence": "/affected/0/package/name"
},
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{
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"evidence": "/affected/0/ranges"
}
],
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},
{
"name": {
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{
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"severity": "high",
"structured": {
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"aliases": [
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"metrics": [
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}
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"affected": [
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"package": {
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"ecosystem": "Debian:12"
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"package": {
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{
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"package": {
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},
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},
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},
{
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],
"package": {
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"purl": "pkg:deb/debian/xwayland?arch=source&distro=forky",
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},
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},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-23T18:03:32.855844722Z",
"provider": "osv",
"upstream": [
"CVE-2021-4011"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2021-4011"
]
},
"related_cves": [
{
"value": "CVE-2021-4011",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 421871,
"published_at": "2021-12-17T17:15:13.53+00:00"
}